The initial danger is over, but Civil Defence says if East Cape residents feel another long, strong quake they need to head for higher ground and as far inland as possible.
A 7.1 magnitude tremor was felt throughout the North Island after is struck at 4:36am on Friday, 130km from Te Araroa in the Pacific Ocean.
Little damage has been reported so far, but residents are being encouraged to check for cracks and report them immediately.
Bay of Plenty District Health Board officials found slight damage to Whakatane Hospital, but none to Tauranga Hospital.
About 1000 homes lost power temporarily in the eastern Bay of Plenty.
A potential tsunami warning was lifted around 8:30am.
Aftershocks have continued to rattle coastal communities, and Civil Defence controller John Clark says residents need to remain vigilant.
"We've discouraged people from playing around on the beach - not that it's beach weather at the moment - and also to think twice perhaps about undertaking small boating activities offshore."
Mr Clark says it's a good time for East Cape residents to check in on their neighbours, especially if they live alone.
There have been more than 100 aftershocks measuring 3.0 or above. Scientists say they could continue for years, based on what happened after 1995's 7.2 quake in the same region.
"The aftershocks for the 1995 earthquake continued for around two years, and since this earthquake is similar in size it will likely have a similar aftershock sequence," says Dr John Ristau, GeoNet seismologist.
"The largest aftershock for earthquakes like this are typically about one magnitude unit smaller than the main shock, and we have had a 6.2 aftershock."
He says Friday's quake was strong, but not strong or shallow enough to cause a damaging tsunami.
Motorists are warned to be cautious on State Highways 2 and 35 because of rock falls and slips. Contractors are monitoring the situation. The New Zealand Transport Agency says people should not stop under the cliffs and be careful of rocks on the road.
Auckland-based WeatherWatch analyst Philip Duncan was woken up by the quake, concerned at the severity of the shaking hundreds of kilometres away from the epicentre.
"I knew this was a big earthquake and I knew it was offshore, and I was concerned about it being a tsunami-type event. It was 55km deep which does usually put it too far down, but it was certainly borderline."
GeoNet received thousands of reports of shaking from around the country.
The Earthquake Commission has given people three months to lodge a claim from Friday's earthquake.
It's urging residents to take action to make their homes safe, sanitary, and weather-tight - and record any work done.
General manager of customer and claims Trish Keith says the first priority for people is to make sure families and friends are safe before worrying about making a claim.
People in Edgecumbe and the rural area between Tarawera and Whakatane Rivers are urged to boil their water before use, due to high amounts of sediment in the aquifers.
Gisborne Mayor Meng Foon says there were no reports of damage initially in his town, but council contractors will be checking infrastructure throughout the day.
Newshub.
